Kristaps Porzingis was looking forward to a day off in Miami. A little sunshine, vitamin D and some R&R may be just what he needs.

Porzingis was low on energy in the Knicks’ 121-103 loss to the Wizards on Wednesday night. After he scored just two second-half points, Porzingis said he was “so tired,” which raised some eyebrows and questions about whether he can carry the load of being the Knicks’ franchise player for a full season.

This wasn’t the first time the 22-year-old has complained about being tired. He said it a couple of times earlier in the season, and three times following games in the past week. Porzingis acknowledged the increased workload is wearing him down.

“That, and also little bumps and bruises and things like that that you play through affects you a little bit,” Porzingis said. “Once I’m playing I want to delete that completely out of my head and not think about it. As you go forward, more and more stuff adding [up], but it’s normal.

“It’s nothing to keep complaining about. We just have to keep pushing forward, get as much rest as I can and try to be as fresh as I can for every game.”

No one said replacing Carmelo Anthony as the Knicks’ go-to guy was going to be easy, but the fact that Porzingis is mentally and physically tired when the Knicks haven’t even reached the midpoint of the season is not a good sign. He has only played in 32 of their 38 games.

If the Knicks are going to stay in the playoff race, they need Porzingis to be strong and healthy as the games become more intense. But the Knicks (18-20) have been on the decline lately, and if it continues, they won’t be playing meaningful games in the spring.

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The loss in Washington was the Knicks’ sixth in seven games, and dropped them two games under .500 for the first time since they were 1-3. Not coincidentally, Porzingis hasn’t been as effective or efficient during this skid as he was at the start of the season.

Over the last eight games, Porzingis is shooting 54-for-150 (36 percent), hitting just 25 percent of his threes (8-for-32) and is averaging 19 points. In the last two games, against the Spurs and Wizards, Porzingis was 10-for-32 and totaled 29 points, including just two in the fourth quarter.

Porzingis is learning that when you’re the focal point of the offense, you’re also the focal point of the defense. It’s been even tougher since Tim Hardaway has been out the last month with a stress injury in his lower left leg.

“A team like San Antonio, I felt like they were all focused on what I was doing so wherever I went there was contact there,” he said. “Having Tim out doesn’t make stuff easier. Hopefully Tim can be back with us soon and kind of take a little bit of pressure and attention off of myself and other guys.”

Opponents are playing Porzingis differently than earlier in the season when he looked more than ready to fill Anthony’s shoes. They’re being more physical and throwing a variety of defensive looks at him. Porzingis is learning how to deal with the different defenses and still be productive.

He scored 30 points or more in eight of the Knicks’ first 11 games, and averaged 30.4 points in that span. In the 21 games he’s played since then, Porzingis has reached 30 three times and is averaging 20.4 points.

No one could have expected Porzingis to maintain the pace he set at the start of the season. Coach Jeff Hornacek believes this is all part of Porzingis’ growth and development.

“Sometimes it’s hard to judge a guy on the first 10 games where all of the sudden you’re really hot,” Hornacek said. “Was that his normal? I think we all wanted it to be the normal. But he is 22, learning how to be in that role. He’s going to have some great nights, he’s going to have some rough nights. He’s just going to play through those.

“I don’t think it’s anything different. Some nights you end up making them. Sometimes the hoop looks really big. Other nights it looks like you can barely fit the ball in there. I don’t think he lets it get him down on those nights. Usually he comes back and bounces back pretty well.”

Kristaps Porzingis has cooled off considerably after a red-hot start to the season:

Al Iannazzone has been covering the Knicks and the NBA for Newsday since January 2012 after following the NBA for 11 years for The Record (N.J.). Al appeared regularly on the YES Network's Nets pregame show in 2005-11.